1. Field of the Invention
The present invention relates to a method for producing a component from a composite material comprising a metal matrix and incorporated intermetallic phases, i.e. from a so-called MIC composite material (MIC: Metal-Intermetallic Composite). The present invention furthermore relates to a corresponding component, in particular consisting of a molybdenum alloy with incorporated silicides.
2. Discussion of Background Information
In turbomachines, such as static gas turbines and aircraft engines, the materials used must satisfy stringent requirements in various property ranges depending on the field of use, for example the lowest possible weight together with high strength, high-temperature stability, vibration stability etc. Correspondingly, there is a need to develop new materials which comply with the demanding property profile for use in static gas turbines or aircraft engines. However, materials which have high strengths at high temperatures are often difficult to process, so that great outlay and therefore high costs are entailed in the production of corresponding components. This is, inter alia, often because such materials have only a low deformability, which makes the component manufacture more difficult.
For example, molybdenum alloys with portions of silicon and boron as well as further alloy elements, which forms intermetallic phases such as silicides, are advantageous for use in high-temperature environments, since they have melting temperatures of more than 2000° C. and possess suitable mechanical properties. However, the production of such MIC materials based on molybdenum is difficult to carry out and very elaborate.
Thus, attempts have already been made to produce by mechanical alloying, from powders which respectively consist of a chemical element corresponding to the desired composition, powder particles which have the desired chemical composition of the material, in order then to process the latter by compaction and sintering as well as hot isostatic pressing and extrusion to process a corresponding component.
However, the mechanical alloying is elaborate and during mechanical alloying, for example by grinding, the auxiliaries used, such as grinding containers, grinding balls, grinding auxiliaries and the like, introduce extraneous substances into the powder so that the material is contaminated.
Furthermore, attempts have also been made to produce from pure elemental powders, i.e. powders which comprise only particles of a single chemical element, by compaction, then sintering and spraying of a corresponding material block, to produce powder particles which have the desired chemical composition in order to produce a corresponding component with these powder particles by generative production methods such as selective laser melting, or by extrusion or by conventional powder-metallurgical shaping. In these methods, however, the problem arises that impurities can be introduced into the metal during the spraying, for example by oxidation, gas inclusions or the like. Furthermore, this method with the various method steps of mixing the elemental powders, compacting, bonding and inert-gas spraying and subsequent powder-metallurgical shaping with recompaction, is very elaborate.
In view of the foregoing, it would be advantageous to have available a method for producing components from so-called MIC materials (composite materials of a metal matrix and incorporated intermetallic phases, so-called metal-intermetallic composites) and in particular from molybdenum alloys with incorporated silicides, with which contamination of the material can be substantially avoided or at least reduced and the production can be simplified.